AD4114 datasheet(21/49 Pages) AD

21 / 49 page

Data Sheet

AD4114

Rev. 0 | Page 21 of 49

ABSOLUTE INPUT PIN VOLTAGES

The AD4114 voltage input pins are specified for an accuracy of

±10 V, specifically for the differential voltage between any two

voltage input pins.

The voltage input pins have separate specifications for the

absolute voltage that can be applied, and the unique design of

the voltage divider network of the analog front end enables

overvoltage robustness on the AD4114, which means the

allowed overvoltages vary depending on the AVDD supply.

Figure 27 and Figure 28 show the different degrees of

robustness that can be achieved for AVDD = 3 V and AVDD =

5 V, respectively. Figure 27 and Figure 28 provide a visual

representation and guidance on how an overvoltage on a

voltage pin can affect the overall device accuracy.

The guaranteed accuracy section of Figure 27 and Figure 28

shows the voltage range that can be applied to a voltage input

pin and achieve guaranteed accuracy.

The no loss of accuracy sections show the voltage levels that can

be applied without degrading the accuracy of other channels.

The no damage to device sections show the allowable positive

and negative voltages that can be applied to a voltage input pin

without exceeding the absolute maximum. The performance of

other channels is degraded, but the performance recovers when

the overvoltage is removed. This voltage range is specified as an

absolute maximum rating of ±65 V.

Operation beyond the maximum operating conditions for

extended periods can affect product reliability.

ABSOLUTE MAXIMUM RATING

NO DAMAGE TO DEVICE

GUARANTEED ACCURACY

NO LOSS OF ACCURACY ON OTHER CHANNELS

+65V

–65V

–17V

–12V

+12V

+19V

AVDD = 3V

Figure 27. Absolute Input Pin Voltages, AVDD = 3 V

ABSOLUTE MAXIMUM RATING

NO DAMAGE TO DEVICE

GUARANTEED ACCURACY

NO LOSS OF ACCURACY ON OTHER CHANNELS

+65V

–65V

–25V

–20V

+20V

+30V

AVDD = 5V

Figure 28. Absolute Input Pin Voltages, AVDD = 5 V

DATA OUTPUT CODING

When the ADC is configured for unipolar operation, the output

code is natural (straight) binary with a zero differential input

voltage that results in a code of 00 … 00, a midscale voltage that

results in a code of 100 … 000, and a full-scale input voltage

that results in a code of 111 … 111. The output code for any

input voltage is represented with the following equation:

Code = (2N × VIN × 0.1)/VREF

where:

N = 24 (the number of bits).

VIN is the input voltage.

VREF is the reference voltage.

When the ADC is configured for bipolar operation, the output

code is offset binary with a negative full-scale voltage that results in

a code of 000 … 000, a zero differential input voltage that results

in a code of 100 … 000, and a positive full-scale input voltage

that results in a code of 111 … 111. The output code for any

analog input voltage is represented with the following equation:

Code = 2N – 1 × ((VIN × 0.1/VREF) + 1)

AD4114 REFERENCE OPTIONS

The AD4114 provides the reference option of either supplying an

external reference to the REF+ and REF− device pins using

AVDD – AVSS as the reference, or allowing use of the internal

2.5 V, low noise, low drift reference. To select the reference

source to be used by the analog input, set the REF_SELx bits,

Bits[5:4], in the corresponding setup configuration register

appropriately. The structure of the Setup Configuration Register 0

is shown in Table 29. By default, the AD4114 uses an external

reference on power-up.

AD4114 Datasheet(PDF) 21 Page - Analog Devices

AD4114 Datasheet(HTML) 21 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49

Datasheet Download

Link URL